Zhu Lingling of Beijing has been anxious to enroll her daughter into an English school of late.

A former athlete, Zhu said she feels a bit embarrassed about her own ordinary English-speaking and reading skills. That's why she wants her daughter Lu Yu, all of three years old and just beginning to say a few words together, to start learning English and get ahead in earnest.

Zhu attended trial classes at four English teaching institutes and finally selected Education First, or EF.

To her surprise, she found the process of enrolling took several months. EF insists on a maximum class size of 10 students. This is to ensure top teaching quality.

At EF, each class has a tutor from so-called native English-speaking countries, who is supported by one local tutor and a teaching assistant. The trio team up to ensure the class is orderly. They also communicate with parents.

Catherine Yang, EF's vice-president, said early-stage education for children aged 3 to 6 is one of the fastest-growing markets in the world for EF, thanks to strong demand from affluent, global-minded and well-informed Chinese parents.

At present, the English learning market for kids in China is estimated at 6 billion yuan ($923 million), with an annual growth rate of 20 percent.

EF operates more than 200 schools for kids and teenagers. EF's early-stage education segment has quickly expanded to second- and third-tier cities.

"Parents born after the 1980s are aware of the golden age for language learning between ages 3 and 6," said Yang.

"We've noticed that non-provincial capital cities also have a great demand for global education, which has supported our growth rate."

EF's English centers focus on creating a language learning environment to eliminate the sense of remoteness of a foreign language, based on interactive communication and social skills.

Compared with fast-growing online learning education entities, a physical environment involving peers and face-to-face communication is better for young people seeking to learn languages, Yang said.

Despite strong demand, business expansion is not EF's priority because ensuring quality of its courses, suitable locations of institutes and full-fledged facilities is more important, she said.

"For example, our classroom doors can be closed but not locked to protect children's safety," said Yang. "Each center is equipped with 360-degree camera surveillance."

The company has provided intensive training for its teaching staff. It also carried out thorough background checks to ensure integrity of its teaching faculty.

China has about 180 million young children aged below 7. According to a report by research company iResearch, Chinese parents in general recognize the importance of kids learning English or any other languages at age 3 to 5.

Research has established that those three years are key to language learning. Hence, about 88 percent of parents choose to enroll their children into English classes well before they turn 5.